1. Technical Field:
This invention relates in general to computer scanners and in particular to a computer scanner for scanning a three-dimensional object in order to acquire a three-dimensional digital representation of the object.
2. Description of Related Art:
As the speed and capability of personal computers (PC""s) has increased, so has the desire to display three-dimensional (3D) representations of objects. In particular, some PC video games allow users to scan their faces onto the characters in the game. Previous scanning devices have used generic bmp-mapping to perform this task with some success. In addition, virtual reality markup language (VRML) allows 3D worlds to be viewed with standard net browsers.
Although PC devices or scanners for scanning two-dimensional objects such as photographs have existed for many years, they have become popular only in the last few years due to lower prices and the capability to scan and represent colors. There are also a few 3D scanners currently available. Currently, 3D scanners are very expensive compared to 2D scanners. One type of 3D scanner employs a laser and a large rotating sensor to quickly generate a full 3D image of an object.
Another 3D xe2x80x9cscanningxe2x80x9d technique also uses a physical 3D model of an object. The designer draws a xe2x80x9cmeshxe2x80x9d of polygons (usually triangles) directly on the model. The polygons cover the entire surface of the model. Large flat surfaces are simulated with large polygons, while areas that need more 3D detail are simulated with smaller polygons. The model is fixed to a stable surface and the designer uses a digital stylus to point to each vertex in the mesh. The stylus is connected to an extensible, multi-jointed sensor arm. As the tip of the stylus is articulated to the various surface points on the surface of the object, the precise angles formed by the joints of the arm at each point are fed to a PC. The PC uses the data to form an electronic 3D representation of the object. Although these, designs are workable, they are complicated designs and either prohibitively expensive or time consuming for most users. Thus, a more affordable 3D scanner that is, easy to use is needed.
A personal computer scanner for scanning the three-dimensional (3D) objects has a frame with an axis, and a front plate. The front plate has a large array of axial pinholes that each contain a slidably movable pin to form a bed of pins. A detection device is slidably mounted near the rear of the frame. A stepper motor is used to move the detection device relative to frame. The detection device has a sensor plate on its front surface with an array of sensors that correspond one-to-one with the pins.
The user selects an object to be scanned and inserts it into the bed of pins to form an impression. The pins readily move and comply to the contours of the object. After the impression is made, the detection device is slowly incremented by the stepper motor toward the pins. The individual sensors are monitored by a host computer until they have been contacted by their respective pins. When a sensor has been touched by its pin, the sensor is scanned by the computer to record the displacement of the pin. This step is repeated until each paired sensor and pin make contact. With this information, the host computer digitally reconstructs the surface of the object scanned based on the displacements of the pins.